The present invention relates to a protecting device for a teat localizer. This device comprises a housing having walls, and being adapted to accommodate the localizer.
Such teat localizer is normally used to localize and establish the position of the udder and teats of a milkable animal in relation to an apparatus used to attach teat cups to the teats when the animal is to be milked. Such apparatus may be part of an automatic milking system and may comprise a milking robot arm.
In the context of the present invention the xe2x80x9cmilkable animalxe2x80x9d may of course be a cow. However, any other milkable animal, such as a sheep, goat, horse or buffalo, may also be intended.
WO 97/15900 (re: Teat Location for Milking) relates i.a. to a milking apparatus support guide arrangement comprising a light source and a video camera cooperating therewith to capture an image and provide an image signal. This signal is then analyzed (by processing means) and a target teat is selected and its position determined to home in said support and any supported milking apparatus to said target teat.
In one embodiment of said arrangement, the light source is a laser mounted in a block constituting a housing in which the camera is also mounted. The laser and the camera are received in a bore and an aperture, respectively, in said block. The block or housing does not provide any effective protecting device for the teat localizer (consisting of the laser and camera) in a difficult environment.
In WO 99/03064 there is disclosed an animal related apparatus for automatically performing an animal related operation, comprising a robot arm supporting a camera and a light source. There is not provided any protecting cover or housing for the light source and/or the camera and its lens.
A first object of the present invention is to provide a protecting device for a teat localizer, which device is able to secure proper function and operation of the localizer in a moist environment, when the function of the localizer is based on the principle of illuminating the teats to be localized and obtaining images thereof by some viewing means.
Another object is to avoid the emergence of moisture-related problems within a housing accommodating the localizer, especially problems relating to impeded or obscured light beam paths for the localizer.
In order to attain said objects, the protecting device according to the invention is so designed that at least one of said walls comprises a transparent or translucent wall portion providing an unimpeded or unobscured light beam path for the localizer, and the housing is provided with moisture deposition-preventing means adapted to prevent moisture deposition on at least the inside surface of the transparent wall portion.
The moisture deposition-preventing means preferably comprises a partition wall being arranged within the housing and spaced apart from the inside surface of the transparent wall portion, said partition wall and at least parts of the walls of the housing defining together within the housing a through-flow gas chamber having a gas inlet means and a gas outlet means allowing a moisture-removing gas flow to be maintained past and close to said inside surface.
To enhance the moisture removal effect of the gas flow within the through-flow gas chamber, suitable flow-guiding means (e.g. guide vanes, tubes or flow nozzles) may be arranged in said chamber. These flow-guiding means may be arranged to provide a more concentrated gas flow along by the inside surface (of the transparent wall portion) in the specific region thereof, where the viewing means should have a completely free line of sight through the transparent wall portion.
A suitable teat localizer may comprise an illuminator and a viewing means. The illuminator may be an ordinary source of light or a laser, and the viewing means may be a video camera (e.g. a CCD-camera or a digital camera) or a laser sensor. The illuminator and at least the lens of the viewing means should preferably be arranged within the through-flow gas chamber.
The gas inlet means may be an inlet opening in one of the housing walls, a gas supply channel or a hose, the outlet end of which communicating with the through-flow gas chamber. The gas outlet means may be an outlet opening in one of the gas chamber walls, preferably in the top wall adjacent to the housing side wall being provided with the transparent wall portion.
To establish a necessary and sufficient moisture-removing gas flow through the through-flow gas chamber, said inlet opening may be connectable to a positive pressure source (e.g. a compressed-air hose) or to an atmospheric gas supply. In the first case, the outlet opening may communicate directly with the interior of the room (e.g. the milking room) surrounding the protecting device housing; and in the second case, the outlet opening should be connectable to a negative pressure source.
When the protecting device according to the present invention is used in an automatic milking system comprising a milking robot, the housing of the protecting device may preferably be mounted on the robot arm.